Abstract: In order to investigate the influence of smoking regime on deliveries of major phenolic compounds in mainstream cigarette smoke,a method for rapidly determining the catechol,hydroquinone,resorcinol,phenol,o-cresol,p+m-cresol in mainstream cigarette smoke by ultra performance liquid chromatography was established.The seven phenolic compounds in mainstream smoke of 38 cigarette samples smoked separately under ISO and Health Canada smoking regimes were tested.The results indicated that:1) The recoveries of the phenols were from 94% to 102% with the relative standard deviation of less than 4% and the limits of detection of 16 to 43 ng/cig.2) The yields of major phenolic compounds in mainstream cigarette smoke under Health Canada regime were significantly higher than those under ISO regime.